Jan, you always know how to stroke my ego!
The following posting is adapted from something of mine the Australian
Carnivorous Plant Society published in their organ, the Bulletin of the
ACPS. I apologize to Terry Bertozzi if my cross publishing it here is a
violation of rules of that society. I also apologize about the sloppy
formatting of this article, this is a translated format...
_Ibicella lutea_: Yet Another Note on the
Carnivore from the Martyniaceae
I have enjoyed the recent flurry of articles regarding _Ibicella lutea_
(for example, Bertozzi 1993; Cekic 1993; Kane 1993). But there is a
small amount of misinformation in these otherwise fine articles. It is
clear the plant Kane (1993) described is not _Ibicella lutea_ (because
of flower colour) but is probably _Proboscidea louisianica_. Seed
obtained from the same source as Kane (labelled ``I. lutea'')
germinated and subsequently flowered---revealing itself to be _P.
louisianica_. Observations of these specimens corroborated Kane's
comments on the plant's ability to capture small insects. But it will
take careful work like that of Mameli (1916) to prove or disprove the
possibility of a carnivorous nature for _Proboscidea louisianica_.
Because of the continued confusion about these plants, I thought I
should write a few words of clarification.
The botanical family that contains _I. lutea_ is _Martyniaceae_.
Various authors---as far back as Van Eseltine in 1929 and continuing
to this day---have disagreed upon the structure of this family. They
have shifted species from one genus to the next, and occasionally
destroyed old genera or created new ones. Through the years, the carnivorous
plant known today as _I. lutea_ has been placed
in three of these mutable genera---_Ibicella, Martynia_ and _Proboscidea_.
Fortunately there is only one plant in the _Martyniaceae_ with the specific
epithet ``lutea''. So if you are reading about species in this
family and encounter _I. lutea, M. lutea,_ or _P. lutea_,
it is the plant that interests the carnivorous plant enthusiast.
There are a few other genera in this family (which are not recognized
by all authors), but they are unlikely to be encountered.
These genera are mostly dryland plants---several species are native to the
desert I live in, and one (_P.parviflora_) was partially domesticated by the
indigenous tribes of Arizona, USA, as a foodcrop that also had textile uses.
The possibly-carnivorous plant, _I.lutea_, is a naturalized weed in southern
California with origins in South America.
Suppose you are growing a plant from this family---how do you know if it
it _I. lutea_, and not some noncarnivorous imposter?
It is simple matter, as long as the plant is in flower.
Look at the calyx (``calyx'' means all the sepals). In
_Proboscidea_ the calyx consists of five sepals which are fused together
for about half their lengths, forming a loose sack which encloses the
corolla tube. Underneath the flower the calyx is usually slit to the base.
If you removed the calyx and flattened it, you would have a palmately-lobed
single structure, like the maple leaf on the Canadian national flag.
In contrast, the calyx lobes of _Martynia_
and _Ibicella_ are completely free from each other---in these two genera,
the calyx consists of five distinct sepals.
At the base of the calyx you will see one or two leafy bracts. Do not
mistake these for calyx lobes.
If your plant has passed the first test, so you are certain it is not
_Proboscidea_, the next step is to determine if it is
_Martynia_ or _Ibicella_. This is decided by the number
of fertile stamens in each flower. _Ibicella_ has four functional stamens,
but in _Martynia_ two are not fully developed and are sterile. These
sterile stamens do not support pollen-bearing anthers. Of course,
the happy CPer is one who discovers he or she has _Ibicella_ and not
_Martynia_. As a final check look at the flower colour.
As Van Eseltine (1929) wrote and Cekic (1993) maintained, the corolla tube
is greenish-yellow on the outer surface, and yellow to orange-yellow
on the inner surface. (This is, of course, what the name _I. lutea_
is telling us.) The palate region of the corolla may be dotted with orange
or red spots, but this is not to say the flower is reddish. The flowers
are very weakly scented, while the flowers of _P. louisianica_
(for example) are strongly musky-sour. Another species of _Ibicella_
is _I. nelsoniana_ (which is sometimes called _Hologregmia
nelsoniana_). This plant is distinguished by its small and
narrow floral bracts, while the bracts of _I. lutea_ are very
similar to the sepals.
A few years ago I was finally able to find a botanical garden where this plant
is grown. A well-placed associate was able to obtain seed from this location
but despite a year's effort, neither of us have yet been able to induce
germination.
A final comment---_I. lutea_ is reported to be more or less
sparsely covered with spines, although specimens I have examined (University
of California at Davis Herbarium) do not bear them. But if _I. lutea_
is often spiny, it is the only carnivorous plant to be so.
References:
Bertozzi, T. 1993. A.C.P.S. Bulletin 12:2, p. 9.
Cekic, C. 1993. A.C.P.S. Bulletin 12:2, p. 7.
Kane, P.M. 1993. A.C.P.S. Bulletin 12:1, p. 12.
Mameli, E. 1916. Ricerche anatomiche, fisiologiche e biologiche
sulla Martynia lutea Lindl. Atti dell'Universita di Pavia, Serie 2,
16, p. 137--188.
Van Eseltine, G.P. 1929. A preliminary study of the unicorn plants
(Martyniaceae): Technical Bulletin 149,
(Geneva: New York State Agricultural Experiment Station), p. 1--41.
Heckard, L.R. 1993. In The Jepson Manual: Higher Plants of California,
ed. Hickman, J.C., (Berkeley and Los Angeles: University of California Press),
p. 762.
Morley, B.D., and Toelken, H.R., 1983. In Flowering plants in Australia,
(Adelaide: Rigby), p. 275.